Comparison of gene expression profile between blood cells and white adipose tissue of patients with obesity

INTRODUCTION Gene expression analyses from peripheral blood mononuclear cells (PBMC) and white adipose tissue are conflicting. It seems that results from single tissue are not enough to explain how changes affect humans as a complex biological system. OBJECTIVE The aim of this study was to compare, from obesity subjects, PBMC and white adipose tissue gene expression that regulates adipogenesis (perilipin 1 [PLIN1], adrenoreceptor beta 3 [ADRB3] and peroxisome proliferator-activated receptor [PPARG2]) and the energy metabolism (uncoupling protein UCP1, UCP2 and UCP3) process. METHODS This study enrolled 35 obese patients, with a body mass index (BMI) > 40 kg/m2 (obesity group [OG]), and ten eutrophic health subjects, 18 > BMI > 24.9 kg/m2 (control group [CG]). Anthropometric and body composition data were assessed at recruitment using standardized protocols. Samples of peripheral blood and subcutaneous adipose tissue (biopsy) were collected to analyze gene expression by RT-qPCR technique. For statistical analysis, we used the Shapiro-Wilk test and Wilcoxon tests by the SPSS software version 20.0; a p < 0.05 significance level was adopted. RESULTS There were significant differences of PLIN1, ADRB3, PPARG2 and UCP3 expression between blood against adipose tissue samples, showing that these genes are upregulated in adipose tissue. UCP2 expression was upregulated in PBMC. CONCLUSION The PLIN1, ADRB3, PPARG2 and UCP3 genes were preferentially expressed in adipose tissue. However, UCP2 was upregulated in PBMC, suggesting that this gene may be assessed in a peripheral blood cell, which is easily accessible, safe and practical.